test line number

javadaima

 

public class Student implements java.io.Serializable {private String name;public static void main(String[] args) {//java.io.Serializable s = new Senior();//s.name="未央华迪";//上一句错误Student s=new Senior();s.name="未央华迪";System.out.println(s.name);}}class Senior extends Student {}class Junior extends Student {}